Topic: Getting the fuel gauge to work?

[dperl]

Alright, so sort of a long story. Let me preface this by saying I'm very very new to electrical work, always seemed out of my league. When trying to fix the fuel gauge, I did a few things out of order that would have saved me trouble, but it's a learning experience.

Anyways, the fuel gauge on my bike never worked, and I figured that would be an easy enough project for me to take on with my limited knowledge. The first thing I did was replace the sending unit inside the tank. I purchased a working one off eBay and after installing, still nothing. After that didn't work, I found out about the 7V regulator the automatics have. Figured it must have been that. Replaced it with something like this

http://www.mouser.com/ProductDetail/STMicroelectronics/L78S05CV/?qs=sepekKm5O7lXLQm2U%2FAl6g%3D%3D&gclid=CjwKEAjwm8-6BRDgnb-Dk96UmRASJADbMycYk-M-q_Na_M8gcnZFZrZ2c22ZfRgy9XT6BK5kMHrkFxoCkonw_wcB

as per this tutorial

https://www.youtube.com/watch?v=naOk1-738Vg

I bought a regulator that can handle a range of voltages from 3V-30V. I don't know if that was a mistake, but once installed, still did not work. I tested the original 7V regulator (which I should've done first, I know, but like I said, I'm new and learning) and I got 11.5v from the black wire and 7.5v from the green / black wire. I believe thats what I should be getting, so now I'm stumped. I measured the wires that you connect to the sending unit on the tank, and got like 70-80 millivolts.

I'm doing all this with no manual and I can't find any info on someone having done this before. I've got a multimeter and a small breadth of knowledge. Any help is greatly appreciated!

[dperl]

Thought I would just update this thread incase anyone is having a similar problem. I got some great help from someone over at the hondamatic.net forums, which surprisingly still is active...somewhat.

Anyways, I have isolated the issue to what I think is a bad 7V regulator. I measured the amount of resistance from the sending unit and it's between 6-10 ohms when the float is at it's highest point and 75-80 ohms at it's lowest point. So thats good. I'm getting 12V going into the regulator, but nowhere near 7V coming out. As per the DIY fix I posted above, I have ordered a small 7V regulator to install and see if that will do the trick!

Will update with progress.

[Gene]

You have a fuel gauge?  Nice.  I have to count the miles . . . hope you get it working.

[dperl]

I do in fact have one. And it's probably the most useless feature on the bike. I've always just referenced the odometer. I actually was able to get it working, but I really don't ever see myself using it. It was more of test and learning experience to see if I could fix it...and I did!

[Gene]

Well Done!